LUM Project

We have a LUM project going on at one inventory org/requisitioning BU and only specific expense subinventories. For the supplier there is a supplier site for EDI and a supplier site for LUM. The majority of our orders are imported from another system that sends all the necessary information including supplier site to generate a requisition in Oracle. Each expense subinventory line item imported has a defined the supplier site. There are different BPAs for the supplier by supplier site. The same items are usually on both BPAs. This is all working well. Where I have an issue is when